GRB 240303B
GCN Circular 35850
Subject
GRB 240303B: Fermi GBM Final Localization
Date
2024-03-03T13:22:09Z (a year ago)
From
rachel.hamburg@ijclab.in2p3.fr
Via
Web form
The Fermi GBM team reports the detection of a likely LONG GRB
"At 12:18:51.24 UT on 03 March 2024, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 240303B (trigger 731161136 / 240303513).
The on-ground calculated location, using the Fermi GBM trigger data,
is RA = 304.49, Dec = 1.26 (J2000 degrees, equivalent to J2000 20h 17m, +1d 15'),
with a statistical uncertainty of 1.00 degrees.
The angle from the Fermi LAT boresight is 96 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2024/bn240303513/quicklook/glg_skymap_all_bn240303513.png
The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2024/bn240303513/quicklook/glg_healpix_all_bn240303513.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2024/bn240303513/quicklook/glg_lc_medres34_bn240303513.gif"
GCN Circular 35851
Subject
GRB 240303B: BALROG localization (Fermi Trigger 731161136 / GRB 240303513)
Date
2024-03-03T13:52:09Z (a year ago)
From
Jochen Greiner at MPE <jcgrog@mpe.mpg.de>
Via
email
T. Preis, B. Biltzinger, J. Burgess & J. Greiner (all MPE Garching) report:
The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
731161136 at 12:18:51 on 03 March 2024 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).
The best-fit position is:
RA(2000.0) = 308.5 deg
Decl.(2000.0) = 1.5 deg
The 1 sigma statistical error radius is 4.5 deg.
We estimate an additional systematic error of 1 deg.
Further details are available at:
https://grb.mpe.mpg.de/grb/GRB240303513/
The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB240303513/healpix
The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB240303513/json
GCN Circular 35857
Subject
GRB 240303B: CALET Gamma-Ray Burst Monitor detection
Date
2024-03-04T02:54:38Z (a year ago)
From
Yuta Kawakubo at Louisiana State University <kawakubo1@lsu.edu>
Via
Web form
S. Nakahira (JAXA), A. Yoshida, T. Sakamoto, S. Sugita (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), Y. Asaoka (ICRR), S. Torii,
Y. Akaike, K. Kobayashi (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U),
N. Cannady (GSFC/UMBC), M. L. Cherry (LSU), S. Ricciarini (U of Florence),
P. S. Marrocchesi (U of Siena),
and the CALET collaboration:
The long GRB 240303B (Fermi GBM Final Real-time Localization: Fermi GBM team,
GCN Circ. 35850; BALROG localization: Preis et al., GCN Circ 35851;
INTEGRAL SPI-ACS: Trigger 10612; GECAM: Trigger 301) triggered the
CALET Gamma-ray Burst Monitor (CGBM) at 12:18:48.35 UTC on 3 March 2024
(http://cgbm.calet.jp/cgbm_trigger/flight/1393503263/).
The burst signal was seen by all CGBM detectors.
The burst light curve shows a multi-peaked structure that starts
at T+2.7 sec, peaks at T+7.2 sec, and ends at T+11.2 sec.
The T90 and T50 durations measured by the SGM data are 5.5 +/- 0.4 sec
and 2.0 +/- 0.1 sec (40-1000 keV), respectively.
The ground-processed light curve is available at
http://cgbm.calet.jp/cgbm_trigger/ground/1393503263/index.html
The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at Waseda University.
GCN Circular 35860
Subject
GRB 240303B: Fermi GBM Detection
Date
2024-03-04T15:41:29Z (a year ago)
From
rachel.hamburg@ijclab.in2p3.fr
Via
Web form
R. Hamburg (CNRS/IN2P3/IJCLab) and C. Meegan (UAH) report on behalf of
the Fermi Gamma-ray Burst Monitor Team:
"At 12:18:51.24 UT on 03 March 2024, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 240303B (trigger 731161136 / 240303513).
The on-ground calculated location is reported in GCN 35850.
This burst was also detected by CALET (Nakahira et al., 2024; GCN 35857)
and the INTEGRAL SPI-ACS (trigger 10612).
The angle from the Fermi LAT boresight is 96 degrees.
The GBM light curve consists of a single bright pulse with a duration (T90)
of about 5.9 s (50-300 keV). The time-averaged spectrum
from T0-1.0 to T0+8.2 s is best fit by
a power law function with an exponential high-energy cutoff.
The power law index is -0.33 +/- 0.03 and the cutoff energy,
parameterized as Epeak, is 540 +/- 20 keV.
A Band function fits the spectrum equally well
with Epeak= 510 +/- 20 keV, alpha = -0.30 +/- 0.04 and beta = -3 +/- 0.3.
The event fluence (10-1000 keV) in this time interval is
(2.31 +/- 0.03)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+3.9 s in the 10-1000 keV band is 18.5 +/- 0.3 ph/s/cm^2.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html
For Fermi GBM data and info, please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"
GCN Circular 35862
Subject
IPN triangulation of GRB 240303B
Date
2024-03-04T18:38:51Z (a year ago)
From
Dmitry Svinkin at Ioffe Institute <svinkin@mail.ioffe.ru>
Via
legacy email
A.S. Kozyrev, D.V. Golovin, M.L. Litvak, I.G. Mitrofanov, and A.B. Sanin
on behalf of the HEND/Mars Odyssey team,
D. Svinkin, D. Frederiks, A. Lysenko, A. Ridnaia,
and T. Cline on behalf of the Konus-Wind team,
A. Goldstein, M. S. Briggs, C. Wilson-Hodge,
and E. Burns on behalf of the Fermi GBM team,
E. Bozzo and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team,
and
W. Boynton, C. Fellows, K. Harshman, H. Enos, R. Starr,
and A.S. Gardner on on behalf of the GRS-Odyssey GRB team,
report:
The long-duration GRB 240303B
(Fermi-GBM detection: The Fermi GBM team, GCN 35850;
Hamburg and Meegan, GCN 35860;
BALROG localization: Preiset al., GCN 35851;
CALET-GBM detection: Nakahira et al., GCN 35857)
has been detected by Fermi (GBM trigger 731161136),
INTEGRAL (SPI-ACS), Konus-Wind, CALET (GBM),
and Mars-Odyssey (HEND), so far, at about 44331 s UT (12:18:51).
We have triangulated this GRB to the following annuli:
---------------------------------------------------
annulus R.A. Dec. R dR (3sigma)
(deg) (deg) (deg) (deg)
---------------------------------------------------
Konus-GBM 320.846 -16.019 24.529 2.743
GBM-SPI-ACS 194.036 78.908 88.157 8.554
GBM-HEND 317.319 -17.507 23.796 0.133
---------------------------------------------------
The annuli intersect to form a long 8.1 sq.deg (3 sigma)
localization region.
The IPN localization is consistent with, but reduces the area of,
the Fermi-GBM final and the BALROG localizations.
This localization may be improved.
A triangulation map and HEALPix FITS file are posted at
http://www.ioffe.ru/LEA/GRBs/GRB240303_T44327/IPN
The Konus-Wind time history and spectrum will be given
in a forthcoming GCN circular.
GCN Circular 35864
Subject
Konus-Wind detection of GRB 240303B
Date
2024-03-04T18:41:13Z (a year ago)
From
Dmitry Frederiks at Ioffe Institute <fred@mail.ioffe.ru>
Via
legacy email
D. Frederiks, A.Lysenko, A. Ridnaia, D. Svinkin,
A. Tsvetkova, M. Ulanov, and T. Cline,
on behalf of the Konus-Wind team, report:
The long GRB 240303B (Fermi GBM detection:
Fermi GBM team, GCN 35850; Hamburg and Meegan, GCN 35860;
CALET detection: Nakahira et al., GCN 35857;
IPN localization: Kozyrev et al., GCN 35862)
triggered Konus-Wind (KW) at T0=44327.406 s UT (12:18:47.406).
The burst light curve shows a bright initial pulse,
which starts at ~T0-0.5s, peaks at ~T0+4s, and has a duration of ~6.5s.
This pulse is followed by a weaker extended emission that lasts
up to ~T0+250s.
The emission in is seen up to ~3 MeV.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB240303_T44327/
As observed by Konus-Wind, the initial pulse had
a fluence of (2.62 ± 0.27)x10^-5 erg/cm^2 and
a 64-ms peak energy flux, measured from T0+4.032 s,
of (1.11 ± 0.12)x10^-5 erg/cm^2/s (both in the 20 keV - 10 MeV energy range).
A time-averaged spectrum of this pulse (measured from T0 to T0+6.4 s)
is best fit in the 20 keV - 15 MeV range
by a GRB (Band) function with the following model parameters:
the low-energy photon index alpha = -0.21 (-0.12,+0.12),
the high energy photon index beta = -2.69 (-0.77,+0.27),
the peak energy Ep = 422 (-49,+61) keV,
chi2 = 92/77 dof.
A spectrum of the extended emission (measured from T0+30.976 to T0+252.16 s)
is best fit by a simple power-law (PL) function with
the PL index of -1.42(-0.22,+0.18), chi2 = 86/99 dof.
A 20-3000 keV fluence in this interval is estimated to (2.42 ± 0.63)x10^-5 erg/cm^2.
All the quoted errors are estimated at the 90% confidence level.
All the presented results are preliminary.
GCN Circular 35873
Subject
GRB 240303B: VZLUSAT-2 detection
Date
2024-03-05T15:05:01Z (a year ago)
From
Marianna Dafčíková at Masaryk University <500025@mail.muni.cz>
Via
Web form
M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), H. Takahashi (Hiroshima U.), F. Munz , M. Topinka, F. Hroch, N. Husarikova, J.-P. Breuer (Masaryk U.), J. Hudec, J. Kapus, M. Frajt, M. Rezenov (Spacemanic s.r.o), R. Laszlo (Needronix), G. Galgoczi (Wigner Research Center/Eotvos U.), N. Uchida (ISAS/JAXA), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), Y. Fukazawa, K. Hirose, H. Matake (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), L. L. Kiss (Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), K. Torigoe (Hiroshima U.), P. Svoboda, V. Daniel, J. Dudas, M. Junas, J. Gromes (VZLU), I. Vertat (FEL ZCU) -- the VZLUSAT-2/GRB payload collaboration.
The long-duration GRB 240303B (Fermi/GBM detection: GCN 35850; CALET/CGBM detection: GCN 35857; Konus/Wind detection: GCN 35864; INTEGRAL/SPI-ACS peak detection at 2024-03-03 ~12:18:56 UT) was detected by the GRB detector on board of the VZLUSAT-2 3U CubeSat (https://www.vzlusat2.cz/en/).
The data acquisition was performed by the GRB detector unit no. 1. The detection was confirmed at the peak time 2024-03-03 12:18:38 UTC. The T90 duration is 6 s and the significance during T90 reaches 27 sigma.
The light curve obtained by VZLUSAT-2 is available here:
https://vzlusat2.konkoly.hu/static/share/GRB240303B_GCN_VZLUSAT2.pdf
We note that the light curve measured by VZLUSAT-2 is shifted by approximately 17 s with respect to light curves obtained by other missions. At the moment, the cause of this discrepancy is being investigated.
All VZLUSAT-2 detections are listed at: https://monoceros.physics.muni.cz/hea/VZLUSAT-2/
The GRB detectors on VZLUSAT-2 are a demonstration payload for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). Two GRB modules of VZLUSAT-2 are placed in a perpendicular manner and each consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~30 keV to ~1000 keV. VZLUSAT-2 was launched on 2022 January 13 from Cape Canaveral.